Answer:
negative impact
Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water. These negative impacts can affect human behavior and can prompt mass migrations or battles over clean water.
positive impact
Environmental regulations have greatly improved air and water quality, especially in areas that were dirtiest before regulation. Reducing airborne particulates is especially beneficial, saving thousands of lives and preventing millions of illnesses each year.